<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 警告信息 -->
      <el-alert
        title="注意：只允许为第三级分类设置相关参数！"
        type="warning"
        show-icon
        :closable="false"
      >
      </el-alert>
      <!-- 选择商品分类区域 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 选择商品分类的级联选择框 -->
          <el-cascader
            v-model="selectedCateKeys"
            :options="cateList"
            :props="{
              expandTrigger: 'hover',
              value: 'cat_id',
              label: 'cat_name',
              children: 'children',
            }"
            @change="handleChange"
          ></el-cascader>
        </el-col>
      </el-row>

      <!-- tab页签区域 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数的面板 -->
        <el-tab-pane label="动态参数" name="many">
          <el-button
            type="primary"
            size="mini"
            :disabled="isBtnDisabled"
            @click="addDialogVisible = true"
            >添加参数</el-button
          >
          <!-- 动态参数表格 -->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开列 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag 
                v-for="(item,i) in scope.row.attr_vals" 
                :key="i" 
                closable
                @close="handleClose(i,scope.row)"
                >
                  {{item}}
                </el-tag>
                <!-- 输入的文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加的按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column label="#" type="index"></el-table-column>
            <el-table-column
              label="参数名称"
              prop="attr_name"
            ></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button
                  type="primary"
                  icon="el-icon-edit"
                  size="mini"
                  @click="showEditDialog(scope.row)"
                  >编辑</el-button
                >
                <el-button 
                type="danger" 
                icon="el-icon-delete" 
                size="mini"
                @click="removeParams(scope.row)"
                  >删除</el-button
                >
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性的面板 -->
        <el-tab-pane label="静态属性" name="only">
          <el-button
            type="primary"
            size="mini"
            :disabled="isBtnDisabled"
            @click="addDialogVisible = true"
            >添加属性</el-button
          >
          <!-- 静态属性表格 -->
          <el-table :data="onlyTableData" border stripe>
            <!-- 展开列 -->
            <el-table-column type="expand">
               <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag 
                v-for="(item,i) in scope.row.attr_vals" 
                :key="i" 
                closable
                @close="handleClose(i,scope.row)"
                >
                  {{item}}
                </el-tag>
                <!-- 输入的文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加的按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column label="#" type="index"></el-table-column>
            <el-table-column
              label="属性名称"
              prop="attr_name"
            ></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button
                  type="primary"
                  icon="el-icon-edit"
                  size="mini"
                  @click="showEditDialog(scope.row)"
                  >编辑</el-button
                >
                <el-button 
                type="danger" 
                icon="el-icon-delete" 
                size="mini"
                @click="removeParams(scope.row)"
                  >删除</el-button
                >
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- 添加参数/属性对话框 -->
    <el-dialog
      :title="'添加' + titleText"
      :visible.sync="addDialogVisible"
      width="40%"
      @close="addDialogClosed"
    >
      <!-- 添加参数/属性的表单 -->
      <el-form
        :model="addForm"
        :rules="addFormRules"
        ref="addFormRef"
        label-width="80px"
      >
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 编辑参数/属性对话框 -->
    <el-dialog
      :title="'编辑' + titleText"
      :visible.sync="editDialogVisible"
      width="40%"
      @close="editDialogClosed"
    >
      <!-- 编辑参数/属性的表单 -->
      <el-form
        :model="editForm"
        :rules="editFormRules"
        ref="editFormRef"
        label-width="80px"
      >
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams"
          >确 定</el-button
        >
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  name: 'Params',
  data() {
    return {
      // 商品分类数据信息列表
      cateList: [],
      // 选中分类信息
      selectedCateKeys: [],
      // 被激活的页签的名称
      activeName: 'many',
      // 动态参数的数据
      manyTableData: [],
      // 静态参数的数据
      onlyTableData: [],
      // 控制添加参数/属性对话框显示与隐藏
      addDialogVisible: false,
      // 添加参数/属性的表单数据对象
      addForm: {
        attr_name: '',
      },
      // 添加参数/属性的表单验证规则
      addFormRules: {
        attr_name: [
          { required: true, message: '该项不能为空', trigger: 'blur' },
        ],
      },
      // 控制编辑参数/属性对话框显示与隐藏
      editDialogVisible: false,
      // 编辑参数/属性的表单数据对象
      editForm:{},
      // 编辑参数/属性的表单验证规则
      editFormRules:{
        attr_name:[
          { required: true, message: '该项不能为空', trigger: 'blur' },
        ]
      }
    }
  },
  created() {
    this.getCateList()
  },
  methods: {
    async getCateList() {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status !== 200) {
        return this.$message.error(
          '加载商品分类数据失败，状态码为：' + res.meta.status
        )
      }
      this.cateList = res.data
    },
    // 级联选择器选择框变化，会触发这个函数
    handleChange() {
      this.getParamsData()
    },
    // tab页签点击事件的处理函数
    handleTabClick() {
      this.getParamsData()
    },
    // 获取参数的列表数据
    async getParamsData() {
      if(this.selectedCateKeys.length !== 3){
        this.selectedCateKeys = []
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      // 根据所选分类的id，和当前所处的面板，获取对应的参数
      const { data: res } = await this.$http.get(
        `categories/${this.cateId}/attributes`,
        { params: { sel: this.activeName } }
      )
      if (res.meta.status === 400) {
        return this.$message.warning('请选择第三级商品分类！')
      }
      if (res.meta.status !== 200) {
        return this.$message.error(
          '加载分类参数信息失败，状态码为：' + res.meta.status
        )
      }
      res.data.forEach(item=>{
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        // 控制文本框的显示与隐藏
        item.inputVisible = false
        // 文本框中输入的值
        item.inputValue = ''
      })
      if (this.activeName === 'many') {
        this.manyTableData = res.data
      } else {
        this.onlyTableData = res.data
      }
    },
    // 监听添加参数/属性对话框的关闭事件
    addDialogClosed() {
      this.$refs.addFormRef.resetFields()
    },
    // 添加参数或属性确定按钮
    addParams() {
      // 验证表单
      this.$refs.addFormRef.validate(async (valid) => {
        if (!valid) {
          return this.$message.error(`错误的格式，添加失败！`)
        }
        const { data: res } = await this.$http.post(
          `categories/${this.cateId}/attributes`,
          {
            attr_name: this.addForm.attr_name,
            attr_sel: this.activeName,
          }
        )
        if (res.meta.status !== 201) {
          return this.$message.error(
            `添加${this.titleText}失败,状态码为：` + res.data.status
          )
        }
        // 关闭对话框
        this.addDialogVisible = false
        // 刷新数据
        this.getParamsData()
        // 弹框提示
        this.$message.success(`添加${this.titleText}成功！`)
      })
    },
    // 展示编辑参数/属性对话框
    async showEditDialog(params){
      const {data:res} = await this.$http.get(`categories/${params.cat_id}/attributes/${params.attr_id}`,{
        attr_sel:this.activeName
      })
      if(res.meta.status !== 200){
        return this.$message.error('加载参数信息失败，状态码为：'+res.meta.status)
      }
      // 获取数据并显示在输入框
      this.editForm = res.data
      // 显示编辑对话框
      this.editDialogVisible = true
    },
    // 监听编辑对话框的关闭事件
    editDialogClosed(){
      this.$refs.editFormRef.clearValidate()
    },
    // 编辑表单确定按钮
    editParams(){
      this.$refs.editFormRef.validate(async valid=>{
        if(!valid){
          return this.$message.error('错误的格式，修改失败！')
        }
        const {data:res} = await this.$http.put(`categories/${this.editForm.cat_id}/attributes/${this.editForm.attr_id}`,{
          attr_name:this.editForm.attr_name,
          attr_sel:this.activeName
        })
        if(res.meta.status !== 200){
          return this.$message.error(`修改${this.titleText}失败，状态码为：`+res.meta.status)
        }
        // 关闭对话框
        this.editDialogVisible = false
        // 刷新数据
        this.getParamsData()
        // 弹框提示
        this.$message.success(`修改${this.titleText}成功！`)
      })
    },
    // 删除参数按钮
    async removeParams(params){
      const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }).catch(err=>err)
      if(confirmResult !== 'confirm'){
        return this.$message.info('已取消删除！')
      }
      const {data:res} = await this.$http.delete(`categories/${params.cat_id}/attributes/${params.attr_id}`)
      if(res.meta.status !== 200){
        return this.$message.error(`删除${this.titleText}失败，状态码为：`+res.meta.status)
      }
      // 刷新数据
      this.getParamsData()
      // 弹框提示
      this.$message.success(`删除${this.titleText}成功！`)
    },
    // 文本框失去焦点，或摁下了Enter键都会触发
    async handleInputConfirm(row){
      if(row.inputValue.trim().length === 0){
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      // 后续处理
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false
      // 发起请求保存这次操作
      this.saveAttrVals(row)
    },
    // 将对attr_vals的操作保存到数据库
    async saveAttrVals(row){
       const {data:res} = await this.$http.put(`categories/${row.cat_id}/attributes/${row.attr_id}`,{
        attr_name:row.attr_name,
        attr_sel:row.attr_sel,
        attr_vals:row.attr_vals.join(' ')
      })
      if(res.meta.status !== 200){
        return this.$message.error('修改参数项失败，状态码为：'+res.meta.status)
      }
      this.$message.success('修改参数项成功！')
    },
    // 点击按钮，切换为文本输入框
    showInput(row){
      row.inputVisible = true
      // 让文本框自动获取焦点
      // $nextTick方法的作用，就是当页面上元素被重新渲染之后，才会指定回调函数中的代码
      this.$nextTick(_ => {
          this.$refs.saveTagInput.$refs.input.focus();
      });
    },
    // 删除参数项
    handleClose(index,row){
      row.attr_vals.splice(index,1)
      this.saveAttrVals(row)
    }
  },
  computed: {
    // 如果按钮需要被禁用，则返回true，否则返回false
    isBtnDisabled() {
      if (this.selectedCateKeys.length !== 3) {
        return true
      }
      return false
    },
    // 当前选中的三级分类的id
    cateId() {
      if (this.selectedCateKeys.length === 3) {
        return this.selectedCateKeys[2]
      }
      return null
    },
    // 动态计算标题的文本
    titleText() {
      if (this.activeName === 'many') {
        return '动态参数'
      }
      return '静态属性'
    },
  },
}
</script>

<style lang="less" scoped>
.cat_opt {
  margin: 20px 0;
}
.el-tag{
  margin:10px;
}
.el-tag:first-child{
  margin-left: 50px;
}
.input-new-tag{
  width: 120px;
}
</style>